The liquid crystal display is a commonly used flat panel display, and the thin film transistor liquid crystal display (abbreviated as TFT-LCD) is a mainstream product in the liquid crystal display.
The thin film transistor liquid crystal display includes a display region and a non-display region, the display region is provided with a plurality of pixel units, each pixel unit is provided with a pixel electrode, a storage capacitor, and a thin film transistor, a first terminal of the storage capacitor is connected to the data line and a source of the thin film transistor, and a second terminal of the storage capacitor is connected to a gate of the thin film transistor or a common voltage line.
The case in which the second terminal of the storage capacitor is connected to the common voltage line is taken as an example. When a gate line corresponding to a pixel unit is scanned, a data voltage signal is loaded on the first terminal of the storage capacitor through a data line, a common voltage signal is loaded on the second terminal of the storage capacitor through a common voltage line, then a voltage difference is generated between the first and second terminals of the storage capacitor, the storage capacitor is charged completely and the storage capacitor is used to maintain the voltage on the pixel electrode of the pixel unit after the scanning of the gate line of the corresponding row is finished.
Currently, the common voltage signal is generally a DC signal or an AC signal. When the common voltage signal is an AC signal, polarity reversion requirements of the liquid crystal molecules in the liquid crystal display may be met as long as the output voltage of the data voltage signal is set to be in the range of 0 to 5V; when the common voltage signal is a DC signal, only when the output voltage of the data voltage signal is set to be in the range of −5V to 5V, the polarity reversion requirements of the liquid crystal molecules in the liquid crystal display may be met.
From the above, when the common voltage signal is a DC signal, the output voltage swing of the corresponding data voltage signal is relatively large (the range of voltage variation is relatively large). If the output voltage swing of the data voltage signal is increased, the power consumed during the storage capacitor is charged or discharged is increased and the power consumption of the entire liquid crystal display panel is increased.